PhD candidate UT Hlth. San Antonio San Antonio, Texas, United States
Disclosure(s):
Emma L. Mask: No financial relationships to disclose
Introduction/Rationale: Different metabolic requirements between autoreactive and non-autoreactive B cells are potential targets of therapeutics to selectively inhibit autoantibody (autoAb) production in systemic lupus erythematosus. Pharmacological inhibition of glycolysis blocks autoAb production in lupus mouse models, but not that of immunization-induced Ab. The goal of this study was to elucidate the mechanisms behind the glycolysis requirements of lupus antigen (Ag) specific B cells.
Methods: Rheumatoid factor (RF)-producing AM14 BCR Tg B cells transferred into BALB/c mice were stimulated with either cognate Ag PL2-3 or TLR7/8 agonist R848. In parallel, NP-specific B1-8 BCR Tg B cells were transferred into BALB/c mice immunized with NP-OVA. Recipient mice were treated or not with 2-deoxy-D-glucose (2DG) to inhibit glycolysis. Bulk RNA-seq of FACS-sorted AM14 and NP+ B cells was performed followed by Ingenuity Pathway Analysis (IPA).
Results: 2DG decreased the production of RF in PL2-3-, but not R848-stimulated AM14 recipient mice. 2DG also decreased anti-NP IgM and IgG in B1-8 recipient mice. However, 2DG induced major transcriptional changes only in PL2-3-stimulated AM14 B cells, in which it downregulated mitochondrial dysfunction, cytokine signaling, phagosome formation, and Inositol Phosphate Compounds pathways, while upregulating the oxidative phosphorylation (OXPHOS) pathway. IPA Upstream Regulator Analyses predicted activation of metabolism-related transcription regulators, MYC and NFAT5, and inhibition of extrafollicular (EF) age-associated B cell (ABC) differentiation regulators, IFN-γ, IRF7, and IL-21. Expression of ABC markers also decreased, consistent with the EF pathway differentiation of AM14 B cells.
Conclusion: 2DG treatment shifts the transcriptional profile of autoreactive AM14 B cells to favor OXPHOS and inhibit pathways related to BCR and endosomal TLR signaling. These results suggest that glycolysis inhibitors may curb the EF differentiation lupus-antigen specific B cells.
